Letoff for narrow ware loom



Oct. 15, 1957 E. R. HOLMES LETOFF FOR NARROW WARE LOOM 2 Sheets-Sheet 1 Filed June 22, 1953 INVENTOR ELBRIDGE R. HOLMES ATTORNEY Oct. 15, 1957 E. R. HOLMES LETOFF FOR NARROW WARE LOOM Filed June 22, 1953 58 65 '1 I 52 as I 35 43 42 M 2 Sheets-Sheet 2 l I 4O 2-H INVENTOR ELBRIDGE R. HOLMES ATTORNEY Ute LETOFF FOR NARROW WARE 1.00M

Elbridge R. Holmes, Worcester, Mass, assignor to Crampton & Knowles Loom Works, Worcester, Mass, a corporation of Massachusetts Application June 22, 1953, Serial No. 363,016 8 Claims. (Cl. 13-Ii1ll) This invention relates to letoif mechanisms for narrow ware looms and it is the general object of the invention to provide an automatic letolf which will permit the weaving of several different webs with groups of warp threads drawn from a relatively long warp beam.

in the weaving of certain types of narrow ware it is desirable to use a wei hted tension member in a well formed in each group of warp threads to insure uniformity of tension. in the past such weighted tensions have been used with small narrow warp beams, one for each web, and friction means has controlled the beams. The friction means prevents turning of the small beam and When the weight rises to a given elevation it lifts a lever which temporarily relieves the friction and the weight is then able to turn the beam to letoft' warp until the weight falls away from the lever, whereupon the friction is reestablished and the weighted member again begins to rise as the beam is held against rotation. in such an arrangement, however, the weight of the beam is quite small and the weight of the tension member in the corresponding well is able to turn the small beam.

'When it is desired to use a long beam to supply warps for several different webs it is found that one weighted tension member may get to a high position before other members do, and if the former letoif controls were used this one tension member would not be heavy enough to turn the long heavy beam.

it is an important object of the present invention to provide feed means between a long warp beam and a plurality of individual weighted tensioning members and provide for positively feedin the warp when a weighted member reaches a given predetermined high position, thus relieving the weighted members from the work or" turning the large beam.

it is another object of the invention to provide warp feed mechanism which will advance warp to increase the depth of the wells in the warp g oups, and provide means for stopping the feeding operation when the wells attain a given depth.

It is a still further object of the invention to turn the feed rolls by means of an electric motor the switch of which is controlled by a weighted member in one of the aforesaid warp wells. When the weighted member reaches a given high position due to consumption of warp in its well it will close the motor switch, whereupon the motor will turn the feed rolls to deliver warp from the warp beam faster than the rate at which it is consumed by the weaving operation, thereby enabling the depth of the well to increase and enable the weighted member to descend to a low position and open the switch. As shown herein control of the motor switch is effected by means of a flexible connector attached to one of the weight members, but this is not the only way in which the rising and falling of the weighted member to its high and low positions can be utilized to control the motor switch.

It is desirable that the rate of warp feeding should not be excessive and in order to produce the desired retardation between the motor and the feed rolls it is a further 2,809,670 Patented Oct. 15, 1957 EQQ object of the invention to provide tween the motor and the feed rolls.

It is a still further object of the invention to lock the feed mechanism during periods of idleness of the motor ltJo prevent the weighted members from turning the warp cam.

in order that the invention may be clearly understood reference is made to the accompanying drawings which illustrate by way of example the embodiments of the invention and in which:

Fig. 1 is a side elevation of a narrow ware loom having the invention applied thereto,

Fig. 2 is a rear elevation, parts being broken away, looking in the direction of arrow 2, Fig. 1,

Fig. 3 is an enlarged vertical section on line 33, Fig. 1,

Figs. 4, 5, 6 and 7 are enlarged vertical sections on lines i4, 55, 6-6, and 77, respectively, Fig. 3,

Fig. 8 is a fragmentary detailed horizontal section on line 88, Fig. 6.

Fig. 9 is a diagrammatic view showing the manner in which a weighted tension member controls the motor switch,

Fig. 10 is an enlarged plan view looking in the direction of arrow 10, Fig. 2, and

Fig. 11 is an enlarged fragmentary View showing the worm and gear connection between the motor and the warp feed mechanism.

Referring to Fig. l, the loom frame 1 supports a lay 2 swinging about a rocker shaft 3 and moved backwardly and forwardly by the usual connectors one of which is shown at 4. The lay is provided with a plurality of narrow ware shuttles one of which is indicated at 5, and these shuttles may be reciprocated in any approved manner lengthwise of the lay by means not shown herein to pass through their respective warp sheds one of which is shown at 6. As shown in Fig. 1, two harness frames 7 form the warp sheds in groups G of warp threads which extend forwardly from a guide 8 which is fixed to the back of the loom.

in carrying the invention into efiect the rear part of the loom is provided with two upright posts 10 and 11 each of which is made of two upright bars 12 and 13 separated by a space 14, see Fig. 2. The bars 12 and 13 may be held in spaced relation in any desired manner and are secured at their lower ends to a bracket 15 made fast with respect to the rear of the loom frame. Braces, one of which is shown at 16, may be utilized to support the posts from the upper part of the loom frame.

Each of the posts 1!} and 11 is provided with a bearing held at the upper end thereof by bolts 21 to support a shaft 22 on which relatively long warp beams are mounted. In the present instance two warp beams are shown at 23 and 24, but more warp beams can be employed if required by the width of the loom. Each warp beam is free to rotate on the shaft 22 and is wound to supply a relatively wide sheet S of warp threads which will ultimately be divided into small groups G.

Each post has a bearing member 25 secured thereto by bolts 26. A lower feed roll 27 is pinned at 28 to a shaft 29 which is rotatable on the bearings 25. Each bearing 25 has a hanger bearing 30 pivoted thereto as at 31 to receive the end of a shaft 32 pinned at 33 to an upper feed roll 34. The upper roll 34 hangs by its weight against the lower feed roll, and gears 35 and 36 keyed at 37 to shafts 29 and 32, respectively, cause the parallel rolls 27 and 34 to turn in unison but in opposite directions to serve as part of feed mechanism for warp sheet S.

Each of the posts ll? and 11 has secured thereto a bracket 33 and a beam 39 which runs lengthwise of the loom from one post to the other and which is supported by the brackets 38. Beam 39 supports hangers 40 planetary gearing bethrough which are strung parallel guide rods 41 and 42. Under the guide rods 41 and 42 are arranged a plurality of individual weighted tension members T each including a pulley or sheave 4} under which passes a group G or'warp'threads, a"hang'er fi4 with-respect to which the V sheave rotates, and a hooked rod or" wire 45 the lower end at which supports a weight 46. Each weighted member T is so"rnade that its total weight can be varied in the usual manner." i

In the matter thus far described the sheet S of warp from beam '23pass'es under feed roll 2'7, then between the two feed rolls andth'en upwardly and rearwardly from the warp feed roll 34 and is then divided into the groups G of warp threads. Each group then passes over the guide 41 and thendown un er; its pulliey 43 and then up over the guide 42 to form a warp well 4-7, and thence down to'the'pr'evio'usl'y described guide 8. V

The actuator niechani's'rrfis provided for turning the feed rolls, this mechahis'ni 'as' sho'wn herein including an electric motor M supported by brackets 59 which are bolted'at 51 tothe post 10.1 The motor is provided with a gear reducer 52 including a worm 53 on motor shaft 54" meshi'ngwithaworin gear 55. 'Gear 55 is fast on shaft .56 which is connected to a coupling 57 on an arm 58 which rotates on an extension 59 of the lower shaft 29. The arm has a hub 60 positioned between a retainer ring 61 on the outer end of shaft extension 59 and hub 62 of a solar gear 63 which is keyed at 64 to shaft 29.

A planet pinion or gear 65 rotates on a stud 66 fixed to the 'arm 58 and meshes with the solar gear 63 and also with a second solar gear 67 which is held in fixed position. The gear 67 is of the ring'type and in order to hold it stationary the'bearing 25'is provided with a cylindrieal shoulder 70 which fits'intothe ring gear 67. The bearing 25 also has a short'arm 71 carrying a pin 72 which extends through and is fastened to the web 73 of. the stationary solar gear 67. The number of teeth on one solar gear is greater by one than the number of teeth on "the other solar gear so that for a single rotation of. arm 58 to revolve the planet gear around the solar gears there willbe a difference of one tooth in the amount of rotation of the solar gear- 63 secured to shaft 29 with respect to the amount of rotation of the stationary solar gear'67, r

Fig; '10 shows the electric switch device which controls the motor and includesa stand 8'1 mounted on one of the brackets 50 and having fixed thereto a stud 81 supporting .a friction wa'she'r '82 and a switch controller 83. The latter is pivoted on the stud and has a short upper arm 84 and a lower longer arm 85. The switch 86 is also supported by'the stand 84) and has an upper button 87 on the top thereof for operation by the short arm 84. and has a lower button'SS on the. bottom there- 7 of. for operation by the longer arm 35. A flexible connector element 89 extends fr'om the longer arm S S tQ the adjacent weighted tension member, designated at T in Fig. 9. The controller 83 is held against the friction disk 81 by nuts 90 threaded on to the stud S1 and will.

retain anyposition to'which it may be moved by the flexible connector 89.

7 When the motor is at rest the worm 53 locks the gear 55v and therefore prevents turning of the planet gear arm S.the elfect of which'istoip'revent rotation of the feed rolls 27iand 34.

In operation it may be assumed that worm 53 has'acted as a lock' to prevent turning ofthe feed rolls and that weaving has proceeded toa point where the wells 47 in the groups G. ofwa'rp threads a'i'e shallow and have at tai-hed. a given'minimum' depth so that the tension members are in high position shown in full lines in Figs. 1 and 9:As: the tension member 'T' reaches its high position it exertsan upward pull on the flexible connector 89 to rock thelcontroller' 83 to the full line position shown in Fig.9,

thereby causing" the long arm 85 to push up on its button 88 to close the switch. By appropriate electric circuit means not shown herein this will'start the motor and turning of the worm 53 will cause rotation of the worm gear 55, shaft 56, coupling 57 and planet gear arm 58 to revolve the planet gear 65 around the two solar gears. The arm 58 will turn in the direction of arrow a, Fig. 7, and will effect a turning of the movable solar gear 63in the direction of arrow 1:, Fig. 7. This solar gear is fixed to shaft 29 which in turn is geared to the upper feed roll, the rolls 27 and 34 will'therefore turn as indicated by arrows c and a, respectively, Fig. 5 to advance the sheet S of warp as indicated by arrows e and cause turning of the warp beam 23, which is free to turn.

The groups G of warp threads leading from the top roll 34 will be fed faster than warp is consumed by the loom and as a result the weighted tension members T will descend with an accompanying increase in the depth of the warp wells 47. When the tension member T reaches the low position shown in dotted lines in Fig. 9, corresponding to the maximum given depth of the associated well, the flexible connector 89 will pull down on the controller 83 and turn it in a clockwise direction as viewed in Fig. 9 to cause the long arm to move away from button 88 and at the same time cause the short arm 84 to depress its button 87. This results in opening the switch 86 and the motor will stop running and worm 53 will again lock the rolls 27 and 34 against further rotation.

As weaving continues warp is drawn out of the wells.

7 weighted tension member T which exerts constant tension on its group of warp threads and rises as weaving proceeds. When weighted member T reaches its high position it rocks the controller 83 to close the switch and start the motor, which may be considered to be actuator mechanism for the feed mechanism. When member T reaches its low position when the maximum given depth of its well is attained it will rock controller 83 to stop.

the motor. The feed mechanism is then held against movement by the lock means which in the present instance is the worm 53 and its worm gear. The locking of- V the feed rolls during periods of idleness of the motor prevents the weighted tension members T from turning the feed rolls or the warp beam. When two or more Warp beams are used their several warp threads will call for the sheet S and be controlled by the feed rolls.

Having now particularly described and ascertained the nature of the invention and in what manner the same it to be performed, whatv is claimed is: V

1. In a letoifrnechanisrn for a'narrow ware loom having a warp beam deliveringa. wide sheet of warp threads which is divided into a pluralityof narrow groups of warp threads each having a wellformed therein between the cloth and the beam, feed mechanism engaging the wide sheet of warp threads, a weighted tension member in the well of. each group of warp threads rising to a high position when the'w'arp beam is at rest and falling to a low positiondue to turning of thewarp beam by the feed mechanism during loom operation, and actuating mechanism for the feed mechanism including a motor controlled 'by a tension member and caused by thelatter when in high position to actuate .the feed mechanism to advance saidsheet of warp-toward'the wells and caused to stop actuation 'of the feed mechanism by said tension member whenthelatter is in low position to .stop advance of said sheet of warp, said feedmechanisrn including a p airiof rolls between Whichthe sheet of warp threads passes and the motor when operating actuates the feed mechanism by rotating the rolls in a direction to move said sheet toward the wells.

2. The mechanism set forth in claim 1 wherein the rolls are parallel and the motor turns a worm meshing with a worm gear which is operatively connected to said rolls, the worm and Worm gear acting as a lock to prevent turning of the rolls when the motor is at rest.

3. The mechanism set forth in claim 1 wherein the motor is of an electric type and the tension member controls a switch for the motor which is movable to either on or off position to cause running or stopping of the motor, and friction means are provided for holding the switch in either the on or off position thereof.

4. The mechanism set forth in claim 1 wherein the rolls are parallel and the motor when operating causes a planet gear to revolve around two solar gears, one of which is stationary and the other of which turns with one of said rolls, the solar gears having diflFerent numbers of teeth, and gears connect said rolls to cause them to rotate in unison but in opposite directions.

5. The letoif mechanism set forth in claim 1 wherein the motor revolves a planet gear around two solar gears one of which is stationary and the other of which moves with the feed mechanism and has a number of teeth different from the number of teeth of the stationary solar gear.

6. The mechanism set forth in claim 1 wherein the motor is of the electric type and has a control switch therefor operatively connected to the tension member by a flexible element which is placed under tension to move the switch when the tension member is in both its high and in its low positions.

7. The letoff mechanism set forth in claim 6 wherein the switch is stationary and a pivoted controller therefor is rocked in one direction to close the switch when the weighted member reaches its high position and is rocked in the opposite direction to open the switch when the weighted member reaches its low position.

8. The letofi mechanism set forth in claim 7 wherein the pivoted controller is connected to the weighted member by a flexible element.

References Cited in the file of this patent UNITED STATES PATENTS 562,989 Waite June 30, 1896 1,786,657 Holmes Dec. 30, 1930 2,169,326 Payne Aug. 15, 1939 2,340,888 Klumpp et a1 Feb. 8, 1944 FOREIGN PATENTS 281,535 Germany May 23, 1912 789,494 France Aug. 19, 1935- 

